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    XG-7100 - 21.05.2-RELEASE (amd64) - strange problem with dhcp connection through switches

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    • stephenw10S
      stephenw10 Netgate Administrator
      last edited by

      The only other thing that can sometimes cause an issue is that because the Eth ports are connected via the switch they all share the same MAC address. If more than one is connected to the remote switch that can cause a problem for some switches. That would still effect both static and dhcp IPs though.

      Try running a packet capture on the LAN to see if the DHCP requests are arriving.

      Steve

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      • J
        jjufl
        last edited by

        Thanks for the tip Steve, I'll check it out.

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        • J
          jjufl
          last edited by

          We did some other test, we seted on outsite switch vlan untaged but we still cant get ip adress from dhcp on B side devices. What it looks like on graph(more specyphic info about ifra):
          Untitled Diagram.drawio (1).png
          We think we will need to replace this devices to other to implement pfsense system in our newtwork.
          Thanks for you time it.

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          • stephenw10S
            stephenw10 Netgate Administrator
            last edited by

            I would not expect the Linksys switch to have VLAN 4091 defined at all. If you have it set as untagged there it might be tagging the traffic coming in in which case it will also need to be set on the port connecting to the KVM. Is that the case? Or is the KVM configured to handle VLAN 4091 directly?

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            • J
              jjufl @stephenw10
              last edited by

              Maybe I presented it a bit wrong, but between the two switches where the tunnel(ISP management this point) is, we don't have vlans so on kvm server there are not vlan setting

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              • stephenw10S
                stephenw10 Netgate Administrator
                last edited by

                OK so neither the Linksys switch nor the KVM server is aware of vlan 4091?

                Then I would expect it to work. Were you able to try running a packet capture on the 7100 for the DHCP requests?

                Steve

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                • J
                  jjufl @stephenw10
                  last edited by

                  That's right. For Linksys and kvm that is transparent. I did test, thats looks like on switch there is a dhcp request from kvm machine but it not response from pfsense.

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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    That's running a pcap on lagg0.4091 on pfSense?

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                    • J
                      jjufl @stephenw10
                      last edited by

                      We caught packets on the pfsense lan interface, but they were only DHCPDISCOVER packets.

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                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        Ok, but importantly it was on lagg0.4091? The LAN is assigned as lagg0.4091?

                        If you captured them on lagg0 for example they may have been incorrectly tagged.

                        If you are seeing the DHCP requests on LAN however the DHCP server should respond unless the requests are somehow invalid. I would expect to see errors in the dhcp log though if that were the case.

                        Do you see a state opened on the LAN for those requests? Perhaps they are being blocked by the firewall somehow?

                        Steve

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